Apparatus for mixing char-ash into coal stream

Abstract

Apparatus for obtaining complete mixing of char with coal prior to the introduction of the mixture into the combustor (30) of a coal gasifier (10). The coal is carried in one air stream (22), and the char in another air stream (54), to a riffle plate arrangement (26), where the streams of solid are intimately mixed or blended.

I claim: 
     
       1. Apparatus for generating low BTU gas from coal, including an entrained coal gasifier having means defining a first combustion zone, means defining a second reductor zone, a plurality of burners firing into the combustion zone, means for introducing combustibles, in the form of mixed coal and char, and oxygen to the combustion zone under substantially stoichiometric condition, means for introducing coal to the reductor zone under substoichiometric conditions, the reductor zone being located such that the hot gases from the combustion zone pass through the reductor zone, generating low BTU gas and char therein, means through which the low BTU gas and the char are discharged from the coal gasifier, means for separating the char from the low BTU gas, riffle plate means, the riffle plate means having an inlet end and an outlet end, the outlet end being connected to the burners, means for introducing char to one side of the inlet end, means for introducing coal to the other side of the inlet end, said riffle plate means including a plurality of first plates secured at the inlet end of the riffle plate means to said one side, and a plurality of second plates secured at the inlet end to said other side, the other ends of both said first and second plates extending inwardly and in a downstream direction to a point past the central axis of the riffle plate means, said first and second plates being of such number that they extend across and cover a major portion of the entire cross-section of the riffle plate means, the first and second plates running alternately with each other, so that their other ends are inter-nested, and thus, the first plates direct a portion of the char towards said other side of the riffle plate means, and the second plates direct a portion of the coal towards said one side of the riffle plate means, so that the coal and char flowing to the burners is thoroughly mixed or blended together. 
     
     
       2. The apparatus set forth in claim 1 wherein the first and second plates each have side members attached to and extending along both sides of each plate.